Abstract

Ultrafast carrier dynamics and saturable absorption of few-layered graphene oxide, well-dispersed in organic solvent, are studied using femtosecond pump-probe and Z-scan techniques. The results demonstrate that few-layered graphene oxide has a fast energy relaxation of hot carriers and strong saturable absorption, which is comparable with that of reduced graphene oxide. Fast carrier relaxation combined with well solution processing capability arises from the large fraction of carbon atom inside the few-layered graphene oxide sheet together with oxidation mainly existing at the edge areas. This superiority of few-layered graphene oxide will facilitate potential applications of graphene for ultrafast photonics.

Received 07 January 2011Accepted 03 March 2011Published online 22 March 2011

Acknowledgments:

This research was supported by Chinese National Key Basic Research Special Fund (Grant No. 2011CB922003), Natural Science Foundation of China (Grant Nos. 10974103 and 50933003), the Program for New Century Excellent Talents in University (Grant No. NCET-09-0484), the Natural Science Foundation of Tianjin (Grant No. 09JCYBJC04300), and the Key Project of Chinese Ministry of Education (Grant No. 109039).